public function testLoaderDumper()
 {
     $conf = new TestConfiguration(['key1' => 'value1', 'key2' => 2, 'key3' => [1, 2, 3, 4]]);
     $dumpFile = sys_get_temp_dir() . '/' . uniqid() . '.cache';
     $conf->dump($dumpFile);
     $this->assertFileExists($dumpFile);
     $conf2 = new TestConfiguration();
     $conf2->load($dumpFile);
     $this->assertEquals('value1', $conf->get('key1'));
     $this->assertEquals(2, $conf->get('key2'));
     $this->assertEquals([1, 2, 3, 4], $conf->get('key3'));
     unlink($dumpFile);
 }